The development of a universal protocol to differentiate any hPSC line into a homogenous population of a specific cell type has been rendered difficult by the inherent variability that exists between lines. Epigenetic memory, inconsistent reprogramming and genetic background are likely to be the main cause of this variability which represents a major challenge for the development of personalised medicines[1, 21] and for modelling diseases with a low penetrance phenotype. The expansion of intermediate stages of differentiation could represent an attractive alternative to address this issue, especially if these cell types can be isolated from a heterogeneous population. For example, Neuronal Stem Cells can be easily expanded from hIPSC lines differentiated toward the neuroectoderm lineage and then differentiated into a diversity of neurones thereby bypassing the need to continuously grow pluripotent cells[2]. However, the same approach with endoderm differentiation has been more problematic since the complex combination of inductive signals controlling the specification and patterning of this germ layer can be difficult to mimic in vitro[3].